* {
    margin: 0px;
    padding: 0px;
}

.mydiv {
    height: 255px;
    width: 250px;
    border: 1px solid black;
    margin: 100px auto;
}

h2 {
    text-align: center;
    border-bottom: 1px solid cornflowerblue;
    line-height: 50px;
    background: lightyellow;
}

input {
    height: 50px;
}

ul li {
    float: left;
    list-style: none;
    line-height: 48px;
    width: 48px;
    text-align: center;
    margin-right: 0px;
    border: 1px solid pink;
}

#btn {
    width: 50px;
    height: 54px;
}

#input1 {
    width: 196px;
    text-align: right;
}

#ul1 {
    float: left;
    height: 150px;
    width: 150px;
}
.active{
    background-color: pink;
}